In this paper was developed a faults library for the steam boiler, the accent being on the study of the situations when faults occur in the burning process (furnace). This library is used in the monitoring and control system, the main object consisting in detection and localization of different faults. The system realise the fault detection in real time, comparison the process response with the response of the other models from the digital library and when are applied the same commands or signals in the same mode that in real process. In the last two sections of the paper was developed the application of fault detection algorithm based on plant model of burning process (included in this paper) and graphical results of fault detection experiments.